Type-writing machine.



T. BROWN; TYPE WRITING MAOHINE. APPLICATION FILED DEC. 29

I Patented July 20,1909.

lNl/E/VTOI? AZQMA, 7. AMI-wk ATTORNEY I A. T. BROWN. TYPE WRITING MACHINE. APPLIUATIQN FILED DEG. 29, 1905.

2 SHEETS-SHEET 2.

ATTORNEY Patented July 20, I909;

ms'rATEs PATENT OF ALEXANDER r. BROWN, or SYRACUSE, NEW YORK.

TYPE-WRITING macnrian.

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Specification of Letters Patent.

llatented July 20,1909.

Application filed December 29, 1905. Serial No; 293,792.

To all whom it may concern:-

Be it known that I, ALEXANDER T; BROWN, citizen of the United States, and resident of Syracuse, in the county of Onondaga and State of New York, have invented certain new and useful Improvements in Typea specification:

My invention relates to typewriting machines and it has-for itsprincipal object to lVriting Machines, of which the following is providean improved device for back step-.

ping the carriage. I

- lily invention consists-1n certain features' of construction and combinations and arrangements of "parts, all of which will be fully 'set' forthherein and particularly pointed out in the claims.

My invention is illustrated in the accompanying drawings in which, I

Figure 1 is ar'ear elevation offas much. of a type-writing machine as-ls necessary to illustrate myinvention. Fig. 2 is a top view of a portion; of the same, the carriage being removed andarent; the 'framework shown in section. 'Fig. 3 isa"'f ragmen tary view.

similar toFig. 1, but showing jthe partsain I the position they, occupy when thebaclrspaccrkey is depressed. p I

My invention is applicable to typewriting machines generally;

The main frame of the nachineshownin the dravings comprises two side plates 1, connected together by a back plate '2. Sand side plates have 1 posts 3; which support a top plate 4 from which rise posts 5 that support a stationary carriage- The rail 6 is groovedjin its upper and lower'ledges to" form raceways in whichrun anti-friction 4-0 balls or rollerspthat-i cooperate with rails 7 and 8 of acarriage, which supp ortsthe usual "roller platens These parts have not been shown in detail asthey may be'of any suitableconstruction a'sfar as the present inven- 1 tion is concerned. The carriage has. secured thereto a feed rack 9,,sa d feed rackmthe present instancebeing secured to the lower carriage'rail 8; The rack 9 meshes with two .gean Wheels 10 and 11, both loosely mounted on'a shaft-12 which is supported byframe plates 13 and 14 which in turn-aresupported bythe top plate 4. The rack 9 is of sutlicientwidth to mesh, with both of the gearwheels 10 and 11. The carriage is driven in letter spaced feed direction'by the gear wheel 11 which is connected inany suitable manner with, a driving spring coiled withm a barrel one letter space distance at a'time'. .pawl is operated 'by a-back spacer key 26 "that is mounted'on the top ofa stem 27' Y which passes loosely through a suitable open- V or drum 15 which is mounted onthe shaft 12.

Any suitable means may be provided forregulatin the tension on the driving spring..'

The step ystep feed of the carriage'is controlled through the gear wheel10 which mounted on the shaft and is connected by a tooth and slot connection with the fixed collar 19 in such *fashion that the collar 20 is free to slide longitudinally of the shaft 18 but is constrained to turn withsaid shaft.

The collars l7 and 20 have ratchet teeth formed on their proximate faces and the collar 20fis normally pressed-into engagemen-t with the collar 17 by'a spring 21. v The construction is suchthat when the carriage ismoved toward the leftthe shaft 18 is normally constrained to turnwith the pinion- 16, but the carriage may be moved to ward the right without turning the shaft .l8,'the,ratchet teeth on'the collars 17 and 20 slipping past one another. In order to hold the shaft 18- against backward rotation a -='ratchet wheel 22 is fixed on said shaft near its forward end and said ratchet wheel is engaged by a retaining pawl 23 that is pivoted to the frame plate 14 at 24 and is held by gravity'in engagement with the ratchet wheel 22. Any suitable escapement wheel maybe mounted on or geared to the shaft 18 and said wheel may be controlled byany suitable feed dogs.

' It will be understood that the machineis equipped with the usual printing keys and;

spacekey and that said feed dogs are operated by any of saidkeys to'permit the carriage to be fed step'-by-step toward. the left.

My back spacer comprises a back spacing "pawl 25that is adapted ijto engage a toothed member that moves in unison with the car- "riage. In the present instance, said pawl operates on the gearwheel 11 and is adapted able to move the carriage'toward the right to turn said Wheel backwards, distance suiting in a keyboard plate 28 that is mounted on the side plates 1. At its lower end the rock shaft 31 which is journ'aled at its for the lever 40 on end in the back approximately position shown in Fig. 3,

ward end in a frame plate 32 and at its rear plate 2. The shaft '31 is provided with a returning spring 33 coiled about said shaft I and connected at one end -to a screw 34 threaded, into the shaft and at the other end to a screw '35 threaded into the back plate 2. The motion of the parts under theimpulse of the spring 33 islimited by a collar 36 secured to the key'stem'27and engaging the under side of the keyboard plate 28. The shaft 31 carries an upwardly extending arm 37 to the upper end of which is pivoted one end of a link 38, the other end of which is pivoted at 39 to a lever 40, which is pivoted on a shouldered and headedscrew 41 (F ig.- 1) thatis threaded into the end of a post 42 (Fig. 2) which is secured to the frame plate 14. The pawl 25 is pivoted to screw 43. Said pawl is formed with an arm 44 to the'upper end of which is secured one end of a spring 45, the other end of which is'secured to an arm.of the lever 40. The tension of the spring '45 tends to move the free end of the pawl 25 toward the gear wheel, 11. The arm 44 is formed with a curved slot, the curvature of. said slot being concentric with the pivot screw 43. The

screw 41 on which the lever 40 is pivoted passes loosely through screw limits the motion both directions by the end into engagement with the screw.

In the normal positions of the parts shown in Fig. l the free end or tooth of the pawl 25 and the centers of the screws41 and 43 are inalinement and thelow'er end of the slot 46isin'engageme'nt with the said slot and said of the slot coming screw 41 and. the free end of the pawl is' thereby held away from the gear wheel 11. When the key 26 is depressed the shaft 31 is locked andLthe lever 40 is drawn to the rocking about its pivot 41. During the first part of the rock- 1ng movement of the lever 4 (),'the pawl 25 engages the-gear wheel the motion of simply rocks inunison with the lever about .the screw 41 as a centerso' that the free'end of the pawl moves directly toward the gear wheel .11 and ,enters the notch between two of the teeth of said wheel. When the awl the former about the-pivot 41 as a center is arrested andin a further motion of the lever 40 said pawl is forced to turn about its pivot 43 against the tension of the spring 45. This motion continues until the upper end of'the slot 46 engages the screw 41 and positively prevents any further rockingof the pawl the gear wheel near the rear end thereof vard the Ilgl'lt' the collar a shouldered and headed ,wa rd with relation of the pawl 25 in key 26.

about its pivot When the parts reach" th s position any further motion thereof would of necessity consist of a rotation ofthe pawl 25' and the lever 40 in unison about the pivot 41. As any such rotation'is prevented by the engagement of the pawl with the "parts are arrested bythe pressure of said pawl upward against the gear wheel. It will be perceived that the re sult of this action is topress the pawl forciblyinto engagement with said wheel, thus wheel and consequently of thecarriage. When the gear wheel 11 is thus turned to- 2O being heldagainst rotation by its connection with the shaft 18, which in turn is held against backwardrotation by the retaining pawl 23, said the rear of-the on the collar l7-until the latter collar has turned through a distance of at least one ratchet tooth and of less than two ratchet teeth, so that the collar 17, the gear 10 and the carriage have positively preventing any overthrow of the been moved one letter space position back- Q tothe shaft 18 and to the escapement wheels controlled by said shaft. The gear wheels lO and 11 being held against IOttltlOIllIl letter space back spacing key26 is released and allowed vto return to normal positionunder the imiulse of the spring 33, the pawl 25 slips out ofthe 'notch'betqveen the teeth of the wheel 11 and is returned will be obvious that the-back spacer key may. be operated as many times as desired I and that the carriage will be moved toward the right a letter space .distance at each actuation of said key. lVhen on a depression of the space key the pawl 25 first engages the wheel 11, the point or tooth of said pawl and the pivot screws 41 and 43 are nearly in alinement and approximately'on a line that is tangent to the wheel 11 at the point of engagement of the pawl,. 'so that saidpawl is nearly on the dead cen-- ter of the lever 40, and consequently said lever 40has a very'high leverage on the wheel. As the parts approach-their final position shown in Fig. 3, this leverage is greatly diminished. It results from this construction that the back spacing'movement 0f. the carriage starts off slowly and increases in velocity, which gives an easy touch to the Various changes in the details of-construction and arrangement maybe made without departing from my invention.

direction, when the to its normal position. It j What I claim as new and desire to secure by Letters Patent, is

In a typewriting machine, the combination-of a carriage, a toothed member that moves withsaid carriage, a back spacer pawl toothed member, a

adaptedto engage said lever to which said pawl is pivoted, a spring -.t ion of a carriage, moves with'said carriage,

prevent overthrew ,ofjsaidr toothed member;

to cause said lever to connected at one end with said pawl zmd'at its other endwithsaid lever, means acting into engagement wit member and saidcarriage. r

, 2. In a typewriting machine, the 'combina a toothed member that a back spacer pawl adapted to engage said toothed member,

lever to which said pawl is pivoted, a spring; connected at one end with said pawl andat its otherend with said "lever, means'acting"? directly on said; lever" for actuating lever-and pawl,- means tion of said ,pawl

engagement with said toothed member,"an

means independent of said toothed member I;

for limiting the motion of-said pawl about other direction to cause said]? its pivot *inthe',

lever to press said pawlforcibly' into engage ment with said toothedmember in order; to

. and saidjca 1a e;

' ration Q' r-f ml' age.

3. Ina typewritangmach naxthe combine-- V a a'ito'othed iiiemberflthat moveswith. said-fcarriage,- a back spacer'pawl adapted to. engage said: -toothed -member,

' V lever to which said pa v'vl pivoted, means for actuating said lever, and'a pivot for said said paw? having "two' abutmentsv ada ted to engage, said pivotand serving to ,limit'tlie motion of said pawl-relatively to said lever in both directions. t

I 4. In a typewriting machine, thecombina tion of a carriage, atoothed member that moves'with said carriage, a back spacer pawl lever,

adapted-to engage said toothed member,

' lever to which said pawl'fis lever, said pawl having a slot through which the ends of the slot engagthe'motion of said pivot passes,

rections.

5. In a typewriting machine, tion of a carriage, 'a toothed wheel geare to said carriage, alever pivotednear sai toothed wheel, a back spacer pawl pivote -to said lever 'and'adaptedto engage said toothed wheel, the pivot points of-said lever independent. of ting .the motion" in .nne direction resssaid pawl forcibly toothed member in order vto prevent overthrow of said toothed for limiting em -mo:- about its pivotfm on ui; Hrectionito hold said pawl normally outuof i pivoted, means the combinaand said pawl being approximately on a line tangent to said toothed wheel at the point of engagement-of said pawl, means for limiting the motion of .said pawl with relasaid lever. Y

f6. Ina typewriting machine, the combinatiorrof a carriage, a toothed member that mnYes-v'vithsaid carriage, a back spacer pawl .1 adaptedtomeans for actuating said lever, the point of said pawland the pivot points of said lever [and pawl being approximately ina straight line'when the parts are i and arranged to move out of a straight line during the operation, whereby said actuating kmeans member in the first part of the stroke and d stroke.-

vvtion of a carriage, a toothed member that .moveswithisaid carriage, a back spacer pawl "adapted to engage said lever to which said :pawl is pivoted, two vg'abutments on said pawl adapted to engage the pivot'of said'lever to' said pawl relatively to said t'ections, a back spacer key in the keyboard of the machine, a rock shaft extending to the hack- 0f the machine and operatedby said key, and acoimection between said rock'shaft and said lever.

lever in both-die tion of a" carriage, a, feed riage, a toothed ,wheel meshing with said rack, ya sha a ratchet -connection between said pinion and turned by said pinion in one direction, a detent for preventing rotation of said shaft in the other direction,

adapted'to' engage said toothed wheel, a lever to which said pawl is abutments for actuating said lever, and a pivot for said or limiting the'rotation of said for actuating said pawl. Signed .at Syracuse, Qnondaga,"and Stateof New York, this 23d day of December A. Di'1905.

in normal position limit the motion of;

8. In ,a typewriting machine, the combinarack on said carfeed rack, aginion that is geared to said feed pawl about its pivot, and aback spacer-key in Q the county of v .tion to said lever, andmeans for actuating engage said toothed member, a I lever to which said pawl is pivoted, and

has a high'leverage on said toothed whereby said leverage decreases during the 7. Ina typewriting machine,t he combina toothed member, a

air

share whereby said shaft is a back spacer pawl 10o pivoted, two 

